The boss of troubled German steel producer ThyssenKrupp on Tuesday has pledged to fix the company's problems after a disastrous investment overseas and corruption allegations.

Chief executive Heinrich Hiesinger said he was axing half the management board and writing down the value of its Steel Americas business in Brazil and the USA by almost half to €3.9bn (£2.4bn) "We need more efficiency, transparency and honesty at all levels," said the former Siemens manager, who questioned the entire leadership model, spoke of "old boys' networks" and said a "great deal has gone wrong in the past".

"The disaster with Steel Americas shows that our leadership culture has failed in many areas of the company," said Hiesinger.

On Monday ThyssenKrupp reported a net loss of €4.7bn (£3.7bn) for the year, mainly due to the Steel Americas business, which it is desperately looking to offload. For the first time in its history the group will not pay a dividend.

The problems of Germany's biggest steelmaker are partly homemade. It invested about €12bn in its Steel Americas plants, which were supposed to give it a foothold in the American market. Instead it left the company in severe financial distress and it has sold assets including stainless steel maker Inoxum, valued at more than €10bn, to fill the hole. Once Steel Americas is sold, only about 30% of group revenue will come from steel, ThyssenKrupp said, raising the importance of its businesses making car parts, factories and elevators. Shareholders approved of the restructuring with shares jumping more than 6%, making them the biggest gainer on Germany's blue-chip DAX index.